Call the Midwife creator Heidi Thomas has revealed that season 12 is set to tackle late politician Enoch Powell's controversial Rivers of Blood speech.
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Back in 1968, the MP caused a political storm after strongly criticising mass immigration during a meeting at a Conservative Political Centre in Birmingham.
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The inflammatory statement, which saw the politician dismissed from the Shadow Cabinet, will influence events that take place in the upcoming series of the BBC drama.
Speaking about her decision to address the political event in the new season, Heidi said: "In the very first episode of the new series, which will probably come out in January if it follows the usual pattern, I realised the timing of that episode coincided exactly with Enoch Powell's Rivers of Blood speech which made a huge difference, and not a very positive difference to race relations in Great Britain.
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"It was a big turning point for our society and the way we spoke of and behaved towards people who had come here from other countries, so that was something we felt we had to tackle," she told RadioTimes.com.
Fans can also expect to see the show revisit a major storyline from season four in the upcoming series. In the same interview, Heidi revealed that the Nonnatus House staff will welcome Rhoda Mullucks (Liz White) back to Poplar.
Fans can expect to see Rhonda return to Nonnatus House
Viewers first met Rhonda in season four when she sought help from Dr Turner for her symptoms of morning sickness. He prescribed her thalidomide, which resulted in her daughter, Susan, being born with birth defects.
The creator revealed that Rhonda is set to have another child in season 12. "We haven't actually been with that family for five years, so we're picking up the pieces for them and it makes for a very special Christmas special," she said.
Call the Midwife will return to screens with a Christmas special in December, while season 12 is expected to arrive in early 2023.
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